Let's get more from dan abrams. Former special agent for the fbi brad garrett. We now know that dzhokhar is answering some questions in writing. The fbi wants to know, is anybody else involved? Right. The real trick is figuring out where his mind is? Why does he want to talk to us? Is he being truthful or not? Getting him over that hump and saying, okay, it's okay to talk to us, it's your only avenue to a better situation maybe. That could take a long period of time. And dan, how much longer can this questioning go on without reading the suspect his miranda rights? They're calling it the public safety exception. Unclear how long they're allowed to do it. In past case, the underwear bomber, for about 50 minutes and a court determined that was okay without a miranda warning. The further ter time is away from the incident itself, the more perilous it is constitutionally. At some point, it doesn't matter. He challenges it later on, the court says, you shouldn't have done it. What happens then is this they throw out his statement. So what? They don't need his statement in They have all the other evidence. This is about getting intellige intelligence, from him. Not a statement they can use in court. The charges expected to be filed. Almost certain to face the death penalty. It will be a death-eligible charge for sure. The use of a weapon of mass destruction would be a death-eligible. The fbi interviewing the older brother if 2011. Some members of congress saying that was a missed opportunity, criticizing the fbi for not keeping their eyes on tamerlan. Hundreds of thousands of versions of him are floating around the country. The fbi go, do a background, sometimes ultimately interview them. Visiting jihadist websites are not against the law. A lot of teens and young adults are doing that. You have to do an assessment if you're an fbi agent. Do you move forward? Do you have enough evidence to move on? If you don't have anything but chatter, you move on to the next one. Should they have come back and visited in when did they know about the six months in russia? The devil is in the details. If someone else were involved, would we know by now? One would think. Only because of everything they've been able to do in the last week from their chuters, phones, the people around them, associates. My sense is, they probably have handle on that. Thank you, let's go to josh

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